Device for generating short waves



July 4, 1933. A. EsAu 1,917,105

DEVICE FOR GENERATING SHORT WAVES Filed July 22, 1930 [22 Vzzfars flra/zamfsau V Patented July 4 1933 I A RAHAMEsAUgbnfinlflin, 'GEaMAnY" nnvron ron eEnEnArING' sii'onm vvAvEs Application m 22,1930;s a m mm,are.' amayjmy a;11929.

- Application has 1 filed in Germany July 25,1929;

V A chief difliculty in the generation' of 1 short waves, as is well known, is toobtain a f 5 sufliciently large outputL of energy. By simply connecting a plur'alitybf tubes in parallel, such as in general use in the generation of long waves, a sufficiently highjoutf put can be--,obtained only in very rare instances and it is necessaryto resort {to all 1 kinds off contri'vances in, order1t0-improve somewhat" the "degree of 'efficiency. 'Also the known counterphase,connection, to which the present inventionrelates, does notroifer the desire'd'result in the customary arrangement.

According to the invention, however, the

output of a plurality of electron tubes operating at counter phase, can beincreased considerably, in that the heating filaments are connected in series through a closed oscillatory circuit adapted to be tuned or controlled and including a series connected inductiveresistance and capacity. With a trial transmit-i ting apparatus thusconstructedit was found that the output could be increased by' this arrangement to fivefold of that, obtainable I without the use of the tuned .or controlled circuit. 7 v i Someembodnnents of the nventlon are 36 shown in the drawingby way of example.

plate or anode. .Between the connection 'A'of' V the anode and the connection G'of the grid there is arranged a capacity C for the puranode, which is completed in known manner 7 by means of the inside capacity ofvthe tube In the arrangement represented 'in Figure l two separate batteriesI-I and H for heating 1 are provided. Thefilaments of. bothtubes are connected in series by means of'the connectionleads V and V Both the batteries H and H thus areconnected in parallel.

. pose of tuning the circuit of the grid and.

With this kind of connection however, two batteries are necessary, for the, sake of not disturbing the'jcondition of symmetry of the arrangement mentioned; According to the invention the circuit adapted to betuned; or

controlledfand consisting of the c'apacity'C and inductance L is cut into-the line V 1 Q5 Thearrangement'shown infFigure 2 differ-s from that shown in Fi gurel-in that only one, heating battery I-I is-presen't, which cutin symmetrically-into the arrangemenn in that 1 y it is placed between the line V and a tapping ofthe-inductance L i V w-" Als'o with the arrangement 3 Figure 3- the c'onditions "of symmetry are n "surediirthat'twocircuitsadaptedtobe tuned y orcontrolled are provided, each of which is;' '55 arranged between' the heatingibattery H and a tube The inductances are designated by L and vL while the capacities are marked line are sosma'll that an exact determination of the various values and thereby a determination of the exact frequency is very difficult. t It is probable that increase incapacity (output) is due to the elimination of Ithein'symmetrics which occur when tubes areconnect ed inparallel. In short wave transmitters Y the connecting in parallel per se frequently does not producean increase in capacity (out- 9 put) -,"since because of the inner tube capacities the working wavelengths of the two tubes are'difierently determined. vAccording to the j 7 present invention, these differences caused by the insymmetries of the arrangement, are

eliminated by means ofthe circuit arranged I infthe connecting lines of the heating filaments. i

It is obvious that the arrangement accord- 1 ing to the invention can operate in alike;

manner, if several groups of. electron tubes,

working at counter ph ase,'are connected parallel, that is ,to say, three times twoitubesl work in parallel.

l'claimz t -m- 1. lA device of the kind described including:

a pair of three element tubes each having a" plate, a grid and a filament, a conductive connection between said plates, a second'conduc-f tlve connectlon between sa d grids ,.a third lit-will be notedthatthe dimensionsof the 7 oscillation circuit arranged in the heating.

conductive connection independent of the said second connection between a terminal of one filament and a corresponding terminal of the other filament, a closed circuit including an inductance and a capacity connected in series, conductive connections each extending between the remaining terminal of a respective filament and the closed circuit, said last connections being connected to the closed circuit betweenthe capacity and resistance and respectively on opposite sides of said resistance, and a heating means for said filaments.

2. A device of the kind described including a pair of three element tubes each having a plate, a grid and a filament, a conductive connection between said plates, a second conductive connection between said grids, a third conductive connection independent of the said second connection between a terminal of one filament and a corresponding terminal of the other filament, a closed circuit including an inductance and a capacity connected in series, conductive connections each extending between the remaining terminal of a respective filament and the closed circuit, said last connections being connected to the closed circuit between the capacity and resistance and respectively on opposite sides of said resistance, and a battery bridged between the third conductive connection and the middle of said inductance.

3. In a device of the kind described including a pair of three element tubes each having a plate, a grid and a filament, a conductive connection between said plates, a second conductive connection between said grids, a third conductive connection between a terminal of one filament and a corresponding terminal of the other filament, a closed circuit including an inductance and a capacity connected in series, conductive connections each extending between the remain ing terminal of a respective filament and the closed circuit, said last connections being connected to the closed circuit between the capacity and resistance and respectively on opposite sides of said resistance, said inductance and capacity each consisting of two sections, a bridging connection extending from a point between the sections of the capacity to a point between the sections of the inductive resistance, and a filament bat tery bridged between the last mentioned point and the third conductive connection y In testimony whereof I have aflixed my signature.

.ABRAHAMESAU.

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